Centering device for well casings or liners



' 1930. M. A. LA vELL-E CEHTERTfiG DEVICE FOR WELL CAS INGS OR LINERSFiled March 21. 1928 INVENTOR MATHEWA. 1.,4 VELLE Patented Aug. 19, 1930UNITED STATES MATHEW A. LA VELLE, or LONG BEACH, 'cALIFoimiA CENTERINGDEVICE FOR WELL CASINGS 0R LINERS .Application filed March 21, 1928.Serial No. 263,339.

-Mv invention is a device for aiding in the is Well adapted to? performprocess of cementing off well casings or liners. Indeep Well drilling,and more especially when drilling for oil, it frequently becomesnecessary after a certain depth of. the hole has been attained, tocement oif a portion or all of the well thus far drilled. Variousconditions account for this necessity, among them being the fact thatfrequently before on is reached, the well passes through what is calleda watenstratum. It is readily apparent that in such a case, some stepmust be taken to prevent the flow of water into the well from thisstratum, as it would otherwise tend to hamper the drilling operation andalso contaminate the oil after pumping started.

This process of cementing is, necessarily carried out by lowering asuflicient length of casing into the well to reach that portionrequiring the waterproofing, and then depositing plastic concretethrough the pipe. Various devices are in use for accomplishing thispurpose; but an inherent disadvantage with this process, is the factthat the casing more frequently than'not, works to one side of the bore,resulting in a deposit of concrete which is thicker on one side of thewell than upon the other, oftentimes to suchan extent that the depositedconcrete on one side of the well is so thin that it cracks and fallsaway and thus offers little or no protection against the fiow of watertherethrough.

It is an object of my invention to provide a device for holding thecasing through which the concrete is to be deposited, centrally of thebore of the well.

It is another object to provide a device of the character described,which is possessed of a certain degree of resiliency, making itadaptable to wells of different and varying diameter. a

It is a further object of the invention to produce a device forpositioning a casing centrally of the bore of a well, which may beeasily and quickly applied to and removed from the casing, and which isof such rigid construction that it is unlikely to be renderedunserviceable through hardusage, and which the services required of 1t.

WVith the foregoing and other objects in View which Will'be mademanifest in the fol pointed out in the appended claims, reference "ishad to the accompanying drawings for an illustrative embodiment of theinvention, wherein: Figure 1 is awertical, sectionalview through a well,showing a string of casing withone of my cementing devices in elevationthereupon, and another shown in vertical section.- I

'Fig. 2 is a topplan view ofone of the cementing devices, and atransverse, sectional view'of ;the casing upon which it is positioned;the plane of section being taken upon the line 22 of Fig. 1, and thedirection of view indicated by. the arrows,

Fig. 3 is atransverse, sectional view-of one of the cementing devicesand the associated casing; the plane of section being taken upon theline 33 of Fig.1, and the" direction of view indicated by the arrows.

Fig. 4 is a transverse, sectional view; the plane of section being takenupon the "line i -40f Fig. 1, and the direction of view being indicatedby the arrows. V

In terms'of broad inclusion, the device of the present inventioncomprises a housing adapted to beslidably received upon a length ofcasing and provided with a cage of resiliently variable diameter capableof engaging the sides of the bore of a well, to position the casingcentrally thereof.

The preferred embodiment of my device "comprises a housing indicated inits entirety by the reference character 6, preferably formed of a pairof spaced rings 7 of equal diameter, and a plurality of rigid webs 8,integral with and retaining the rings 7 in axial alignment. The'rin gs 7areof equal diameter, and are. of such size as to permit them to beslipped over a length of casing 9. I v

A plurality of resilient brackets 11 are rigidly secured at one end 12to the outer surface of one of the rings 7; any convenient fasteningmeans being employed, suchasthe iii) ' the sides 27 of the. bore.

screws 13. It is to be understood however, that the same results will beaccomplished if the brackets 11 are secured to the ring 7 by welding, orin any other manner. The other end 14 of each of the brackets 11, isarranged inside the other ring 7; and the natural resiliency of themetal of which the brackets are formed, urges the end 14 outwards topress against the ring 7 which is provided with a recess 16 withinwhicheach of the free ends 14 seats.

The center portion 17 of each of the brackets 11, is bowed outwards sothat the assembly presents a cage of increased diameter inter-' mediateits ends. Due to the fact that the brackets 11 are rigidly mounted atone end 12 of each, the other ends 14 being slidable within theassociated recesses 16, this cage is of resiliently variable diameter.

The manner of operating my cementing device is substantially as follows:The string of casing is made up by connecting the required number oflengths 9, by means of the conventional sleeves 26. However, before soconnecting the lengths 9, one or more of my ing; and a plurality of leafsprings rigidly secured at one end of each to one of said rings, theother end of each of said springs pressing outwards against the innerface of the other ring, and the center portion of each of said springsbeing bowed outwards to present a cage of increased diameterintermediate its ends.

In testimony whereof I have signed my name to this specification.

A. LA VELLE.

cementing devices is positioned upon as'many of the lengths 9 as isdeemed expedient. It is to be observed that the diameter of the housing6 is such that it may he slipped neatly over the length 9 of easing, butis prevented from slipping from one length of casing to another becauseof the interference of the sleeves 26. v

The length of casing is then lowered into the well, and it will be foundthat the brackets 11, owing to the fact that their center portions 17are bowed outwards, will engage The natural resiliency of the bracketspermits the cage to conform itself to the shape and size of the bore,with the result that the lengths 9 of easing upon which the devices arepositioned, are held centrally therein.

. Arranging the brackets 11 with their free ends 14 on the inside of thering 7., results in their pressing against the casing 9 instead ofagainst the housing 6 as would be the case if the free ends 14 werearranged on the outside of the'associated ring 7. The advantage of thisconstruction ies in the fact that the casing 9 will be hel centrally ofthe bore, regardless of whether or not the rings 7 fit the casingperfectly.

Various changes in the details of construction may be made withoutdeparting from the spirit and scope of the invention as de fined by theappended claims.

I claim:

1. Ina device ofrthe character described, a housing comprising a pair ofspaced rings and a plurality of webs retaining the rings in axialalignment, said housing being adapted to slidably fit upon a length ofcasing; and a plurality of leaf springs rigidly p secured at one end ofeach to one of said

